This invention refers to a sorting unit for belt conveyor plants of the type comprising a first sorting conveyor belt extending among first transmission rollers and revolvingly oscillating around a first oscillation axis extending in parallel and close to one of its longitudinal edge, first actuating means to actuate the first sorting belt and first control means to rotate the first sorting belt around the first oscillation axis, bringing it from a rest position, where it lays horizontally, flush with further conveyor belts belonging to said sorting plant, to a delivery position, where it is transversally sloping and vice versa.
As it is known, belt conveyor plants generally comprise one or more main conveyor lines consisting of consecutive conveyor belt chains, along which sorting units,which can be singly and selectively operated,are interposed in order to properly sort the objects transported by the main conveyor line on different secondary lines.
There are nowadays different kinds of sorting units, each one satisfying specific needs, deriving for instance, from the number and the disposition of secondary conveyor lines on which objects must be sorted. As an example, a known type of sorting unit is basically composed by a flap which oscillates around an horizontal axis, parallel to the longitudinal development of the main conveyor line. The objects carried by this conveyor line should selectively fall on a first and on a second secondary conveyor line, placed below the main line, depending on the position of the flap.
Another known type of sorting unit is represented by a conveyor belt placed downstream a main conveyor line after interposition of a chute.
This conveyor belt extends perpendicularly with respect to the longitudinal development of the main conveyor line, and can be selectively operated in the opposite direction to deviate the objects there conveyed by the chute on secondary conveyor lines, developing in opposite direction, consecutively to the belt itself.
Sorting units, consisting of a conveyor belt extending on the continuation of the main conveyor line and revolving on one of its sides to selectively address the objects to two different secondary conveyor lines, have also been realized. From what has been briefly described,it can be noted that all sorting units known up to now, originate different problems when the corresponding conveyor plant is used to transport and sort, for instance, folded clothings, magazines, or in any case soft objects which shall maintain a predetermined configuration and orientation.
It is easy to imagine, in fact, that a folded blouse or a similar article of clothing, if not adequately packed up in a rigid box, as it is frequently the case, upsets and rolls itself up when it drops from the sorting unit on the secondary conveyor line or, this occurs when the objects fall from the main conveyor line on the sorting unit, if the sorting unit itself is composed by a conveyor belt which can be operated in the two directions.
This drawback is due to the fact that in all sorting units known at present, the object transported is compelled to drop on the corner on the secondary conveyor line or on the sorting unit, or to strike against the surfaces of these latter with a certain angle.